I don't feel like a hero..

You never felt like someone heroic. Never fitting in with the Hero Society, or their standards

You had always seen yourself as the villain of someone's story, rather than their hero. So, of course, you went to the League of Villains in hopes of joining their fight against the Hero Society

Dabi: "So.. you're gonna join us?"

Shigaraki: "Dabi! I've told you countless times before, stop slacking off!"